(1-1/3)X+(1-1/4)*(2000-X)=1400

问题描述:

(1-1/3)X+(1-1/4)*(2000-X)=1400
(1-1/3)X+(1-1/4)*(2000-X)=1400

2/3X+1500-3/4X=1400
100=1/12X
X=1200